Mitoquinol is a ubiquinone derivative that specifically accumulates in mitochondria due to the covalent attachment of the cation triphenylphosphonium. It functions as an antioxidant, preventing lipid peroxidation-induced apoptosis and protecting mitochondria from oxidative damage.

Reference：
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[2]. O'Malley, Y., Fink, B.D., Ross, N.C., et al. Reactive oxygen and targeted antioxidant administration in endothelial cell mitochondria. J. Biol. Chem. 281(52), 39766-39775 (2006).